FIG. 1 is a perspective view of a vehicle to which a conventional wiper blade is mounted, and FIG. 2 is a front view of the conventional wiper blade.
As shown in FIG. 1 and FIG. 2, the conventional wiper apparatus comprises a wiper arm 15 installed at one side of a vehicle body 10 and rotated from side to side by a wiper motor (not shown), and a wiper blade 20 mounted to the wiper arm 15, moved on and contacted with a windshield 12 to wipe it, and provided with a wiper strip 30.
The wiper blade 20 is coupled with the wiper arm 15 and is rotated within a predetermined angle range according to operation of the wiper motor. To this end, a main link 22 of the wiper blade 20 is coupled with the wiper arm 15. A plurality of intermediate links 24 are connected to the main link 22 through pins 25 for uniformly transmitting pressure of the wiper arm 15 to the main link 22. A plurality of sub links 26 are connected to the intermediate links 24 with pins 27 to connect the intermediate links 24 to the wiper strip 30. Also, clips 28 are formed at both ends of the sub link 26 and coupled with coupling grooves formed in the wiper strip 30.
Further, the wiper blade 20 is provided with a joint 29 to reduce a friction force between the main link 22 and the intermediate links 24.
In the wiper blade according to the prior art, however, a process of assembling a wiper strip as well as a structure for securing it are complicated, whereby there is a problem in that a time required for assembling the wiper blade is increased to lower a productivity of the articles. Also, in the conventional wiper blade, since the links are moved relative to each other when the wiper blade is operated, noises can be generated in the operation of the wiper blade. In addition, in the conventional wiper blade, the wiper blade is lifted up from the windshield by the wind when the vehicle is driven at a high speed, which causes a contacting force between the wiper blade and the windshield to be lowered. Accordingly, in order to solve the above problem, the structure in which an additional windbreak rib is provided on the main link has been proposed. However, a complete solution has not been proposed, so that there is a room for improvement of the wiper blade.
Technical Problem
The present invention is conceived to solve the aforementioned problems in the prior art. An object of the present invention is to provide a wiper blade, which has a wiper frame formed to have elasticity, has an improved structure for securing a wiper strip, causes a wiper strip to be directly coupled with the wiper frame, and is easily assembled, thereby saving a time required for an assembling process and having improved durability and contacting force, a jig for heat treating a wiper frame of a wiper blade and a method for machining a wiper frame using the same.
Technical Solution
According to an aspect of the present invention for achieving the object, there is provided a wiper blade for wiping a windshield, comprising a wiper strip in contact with the windshield, the wiper strip having rail grooves formed on both sides thereof; a wiper frame curved along its lengthwise direction and having elasticity to bring the wiper strip into contact with the windshield; a coupling slit formed in the wiper frame, the rail grooves of the wiper strip being slidably fitted to the coupling slit; and a coupling aperture formed in one end of the coupling slit and allowing the wiper strip to be inserted thereinto. Here, the wiper frame may have at least one coupling slit and the wiper strip may be formed corresponding to the coupling slit. In addition, any one of a through-hole and a protrusion may be formed between the coupling slits, and then, the other one of the through-hole and the protrusion may be formed in an upper end of the wiper strip to be inserted thereinto. Further, the wiper blade may comprise an auxiliary slit which is connected to an end of the coupling aperture and formed collinearly with the coupling slit. In addition, the coupling aperture that is connected to the coupling slit may be formed to be inclined in the fitting direction of the wiper strip. In the meantime, the wiper blade may further comprise a connector provided at one side of the wiper frame to be coupled with the wiper arm. Preferably, the wiper frame may be formed with a seating portion for guiding a connecting position of the connector. In addition, the wiper frame may be configured such that an area of one side of the wiper frame is increased as it goes to its center. Further, in a case where the wiper frame is arranged to be inclined at a predetermined angle, the wiper strip may be formed to be inclined with respect to the wiper frame to be brought into perpendicular contact with the windshield. Also, the connector to be coupled with the wiper frame may be formed to be inclined in the direction opposite to the inclination direction of the wiper frame.
According to another aspect of the present invention for achieving the object, there is provided a jig for heat treating a wiper frame of a wiper blade, comprising a first jig provided with a first working surface having a predetermined curvature to press an upper portion of a wiper frame workpiece; a second jig arranged opposite to the first jig and provided with a second working surface having a curvature corresponding to the first working surface to press a lower portion of the wiper frame workpiece; and a press for pressing the first and second jigs to form the wiper frame workpiece disposed between the first and second jigs.
Further, the first and second jigs may be provided with a heating means. Furthermore, the jig may further comprise an auxiliary jig disposed between a plurality of wiper frame workpieces placed between the first and second jigs, the auxiliary jig having a curvature corresponding to the first and second working surfaces.
According to a further aspect of the present invention for achieving the object, there is provided a method for manufacturing a wiper frame of a wiper blade, comprising the steps of heat treating a workpiece made of steel to obtain martensite; blanking the workpiece heat treated in the heat treating step to prepare a wiper frame workpiece for a wiper blade; piercing the wiper frame workpiece prepared in the blanking step to remove an unnecessary portion from the wiper frame workpiece; bending the wiper frame workpiece to be formed to have a predetermined curvature; and heat treating and forming the wiper frame workpiece to have a desired curvature by pressing it and simultaneously to relieve internal stress thereof through annealing.
Also, the step of heat treating may comprise the steps of heating the wiper frame workpiece at a transformation temperature or more; and rapidly cooling the wiper frame workpiece heated in the heating step.
Advantageous Effects
According to a wiper blade, a jig for heat treating a wiper frame of a wiper blade and a method for machining a wiper frame using the same of the present invention configured as above, there are the advantages in that a structure of a wiper frame for securing a wiper strip is simple, a process of assembling the wiper strip to the wiper frame is simple, a time required for the assembling process can be reduced, and the manufacturing costs can be remarkably reduced and the durability of the article can be significantly improved since the wiper frame is formed to have predetermined elasticity and therefore no additional part is necessary. It is also possible to form a plurality of wiper frames in a short time using the jig for heat treating a wiper frame.